Mega-E genetic?

[Lauri & The Gang]

I've noticed a couple posts on the board about Mega-E dogs and was wondering - is it known if Mega-E is genetic?

[littledmc17]

I believe it is. I never heard of it until the other day

[MaggieRoseLee]

Yes it is genetic

http://www.caninemegaesophagus.org/G...sposition.html

http://www.vin.com/VINDBPub/SearchPB...00/PR00133.htm

Problem is this condition can be so extreme puppies can die when only a few weeks old, and dogs can also live long healthy sypmtom free lives. To the extent people wouldn't even know their dog had the condition at all.

Added to all the OTHER genetic issues our dogs may have can make this very difficult for breeders. Say you have the perfect temperment in your lines, no hip or elbow dysplasia, but an occasional puppy born with mega? Do you get rid of all the GOOD genetics also by no longer breeding your dog?

[ldpeterson]

It can be.

It can also be secondary to another disease (Myasthenia Gravis, Thyroid issues, Addison's disease or other neuromuscular problems).

It can also be idiopathic meaning there is no explainable reason as to why it showed up at all. This tends to happen in older dogs over 6 years of age.

Although it is a rare disease, no dog is safe from it at any age.

Hope this helps.

[Lauri & The Gang]

Originally Posted By: MaggieRoseLeeSay you have the perfect temperment in your lines, no hip or elbow dysplasia, but an occasional puppy born with mega? Do you get rid of all the GOOD genetics also by no longer breeding your dog?

Tough call but me personally, yes - I would remove that dog from any breeding program and have it's offspring spayed and neutered (if not already done).

Even serious HD can be treated surgically. From what I understand Mega-E cannot.

And while HD will affect the dogs ability to be active, Mega-E can affect the dogs ability to survive.

And there HAS to be at least one dog out there that has the same great qualities as mine but without the Mega-E.

[HeidiW]

I totaly agree with you Lauri stop breeding that dog!!! This is so sad. I don't know what Mega E is so I will read that link.

I have noticed an increased amount of older puppies for sale by breeders because they kept them for show but then changed their minds. I tried to adopt one and he was so Kennel happy he was nervouse in my house and just wanted to be in his outside Kennel all day, which is not what I wanted for him, was not socialized with other dogs. Why add to the over population.

[ldpeterson]

They have found a genetic component in the wirehaired fox terrier and the miniature schnauzer. There has yet one to be found in other breeds affected including the GSD. If there has been new developments since this statement was published please let me know!

This is all very iffy. Sometimes the puppies born with mega just do not have developed nerve function and has nothing to do with genetics. I would not scrap a nice breeding program because one mega pup was thrown, just as a breeder would not scrap an entire breeding program because one dysplastic puppy was thrown. Just as two OFA Excellent dogs can produce dysplasia, two normal dogs can produce a mega puppy.

If it were to keep happening then that would be more concerning. Of course mega dogs should not be bred.

[Chris Wild]

Some research says yes, other says now. It's been proven genetic in some breeds, but not others. GSD being one of those where it's not proven to be genetic.

It's also suspected that there may be different causes to an enlarged esophagus, some genetic and others not. With only symptoms and x-rays to go buy, the fact that the esophagus is enlarged is easy to diagnose, but the actual cause behind it not so much.

This would also explain contridictory research regarding it's genetic base, and also actual experiences of breeders with it. When a high percentage of related dogs are showing MegaE, that would certainly indicate a genetic component. When one odd case pops up as a surprise on rare occasion, that could mean a very complicated polygenic inheritance and that particular pup just lost the genetic lottery, but could also indicate something unique to that pup's development and not genetically based. No one knows for sure.

As Lisa mentioned, idopathic adult onset MegaE seems to be the same sort of condition (enlarged esophagus) as juvenile onset, but likely with completely different (and at this point unknown) causal factors.

[angelaw]

I knew a breeder years ago that seemed to routinely have mega-e. I know it wasn't all of his lines, but out of a couple of dogs. Luckily, he's no longer breeding anymore.

[JeanKBBMMMAAN]

http://www.upei.ca/cidd/Diseases/GI%...aesophagus.htm

I am not sure when they update that or if any new research is available.

"How is megaesophagus inherited?

This is an autosomal recessive trait in the wire-haired fox terrier, and autosomal dominant in the miniature schnauzer. The mode of inheritance has not been determined for other breeds that are predisposed to this condition. "

---

"What breeds are affected by megaesophagus?

Chinese shar pei, German shepherd, Great Dane, greyhound, Irish setter, miniature schnauzer, wire-haired fox terrier.

For many breeds and many disorders, the studies to determine the mode of inheritance or the frequency in the breed have not been carried out, or are inconclusive. We have listed breeds for which there is a consensus among those investigating in this field and among veterinary practitioners, that the condition is significant in this breed."

-----

"Breeding advice

Affected wire-haired fox terriers, their parents (carriers of the trait) and siblings (suspect carriers) should not be bred. Affected miniature schnauzers should not be bred.

In other breeds in which inheritance is unknown, it is safest to avoid breeding affected dogs, their parents and siblings."

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Back to no quotes. This site has good information: http://www.upei.ca/cidd/intro.htm
And the GSD list here: http://www.upei.ca/~cidd/breeds/germanshepherd2.htm

For Myasthenia Gravis: http://www.upei.ca/~cidd/Diseases/ne...a%20gravis.htm
which I had not even realized was in dogs...scary.